The solution:
please download the following file and extract it to the program folder of 3D Train Studio V3, replacing the old file:
https://community.3d-modellbahn.de/applications/core/interface/file/attachment.php?id=53918
The connection error should now be resolved.
From Stefan Werner
Hello.
I have a problem with version 3.
Many elements of the 3d catalog are not available and when placing them in a scene it gives me a connection error, problems with the internet.
If I refresh manually, I get the same error.
Does anyone know the solution?
Thank you.